diff --git a/drivers/ptp/ptp_idt82p33.c b/drivers/ptp/ptp_idt82p33.c
index 223bc11cb8fe..c1c959f7e52b 100644
--- a/drivers/ptp/ptp_idt82p33.c
+++ b/drivers/ptp/ptp_idt82p33.c
@@ -320,7 +320,6 @@ static int _idt82p33_adjfine(struct idt82p33_channel *channel, long scaled_ppm)
 {
 	struct idt82p33 *idt82p33 = channel->idt82p33;
 	unsigned char buf[5] = {0};
-	int neg_adj = 0;
 	int err, i;
 	s64 fcw;
 
@@ -340,16 +339,9 @@ static int _idt82p33_adjfine(struct idt82p33_channel *channel, long scaled_ppm)
 	 * FCW = -------------
 	 *         168 * 2^4
 	 */
-	if (scaled_ppm < 0) {
-		neg_adj = 1;
-		scaled_ppm = -scaled_ppm;
-	}
 
 	fcw = scaled_ppm * 244140625ULL;
-	fcw = div_u64(fcw, 2688);
-
-	if (neg_adj)
-		fcw = -fcw;
+	fcw = div_s64(fcw, 2688);
 
 	for (i = 0; i < 5; i++) {
 		buf[i] = fcw & 0xff;